The overall objective of this proposed research is to define the chemistry of solution catalyzed disulfide cleavage. Several chemical aspects of the catalyzed disulfide yields reversibly dithiol redox interconversion, which are relevant to the enzymatic reaction of "reactive" disulfides, will be studied in chemical model reactions. BIBLIOGRAPHIC REFERENCES: Nucleophilic Cleavage of the Sulfur-Sulfur Bond by Phosphorus Nucleophiles. III. Kinetic Study of the Reduction of a Series of Ethyl Aryl Disulfides with Triphenylphosphine and Water. Larry E. Overman and Stephen T. Petty. J. Org. Chem., 40, 2779 (1975). Nucleophilic Cleavage of the Sulfur-Sulfur Bond by Phosphorus Nucleophiles. IV. Kinetic Study of the Reduction of Alkyl Disulfides with Triphenylphosphine and Water. Larry E. Overman and Edward M. O'Connor. J. Amer. Chem. Soc., 98, 771 (1976).